Late-Summer Roasted Tomato and Basil Soup

By AtheneNet Food Desk | Published 16 August 2026 | AtheneNet

This roasted tomato and basil soup turns 1.5kg of peak-season British tomatoes into four generous servings for an estimated £1.23 each. Roasting concentrates the tomatoes’ natural sweetness, while fresh basil, garlic and a little vinegar keep the finished soup bright without requiring cream or complicated ingredients.

Choose ripe tomatoes that feel heavy and smell fragrant near the stalk. Mixed shapes and sizes are welcome: inexpensive wonky tomatoes, garden gluts and slightly soft fruit all work, provided there is no mould or fermentation.

Ingredients and estimated UK cost

The prices below are an illustrative budgeting guide rather than a live supermarket comparison. Your total will depend on where you shop, whether the tomatoes are home-grown and which cupboard ingredients you already have.

That works out at approximately £1.23 per serving, excluding optional bread, croutons or a spoonful of yoghurt. Buying a larger box of tomatoes at a market or using a garden harvest can reduce the cost considerably.

Use a vegetable stock that suits your dietary needs. Some stock cubes contain gluten, celery or other allergens, so check the label when cooking for someone with an allergy or intolerance.

How to make roasted tomato and basil soup

1. Heat the oven to 220°C, 200°C fan or Gas 7. Set out a large, rimmed roasting tray.
2. Halve the tomatoes, or quarter very large ones. Cut the onion into thick wedges and peel the garlic cloves.
3. Arrange the tomatoes cut-side up in a single layer. Tuck the onion and garlic among them, keeping the garlic beneath or between the tomatoes so it does not scorch.
4. Drizzle over the oil, season with salt and black pepper, then toss gently. Roast for 35–40 minutes, until the tomatoes have collapsed and their edges are beginning to caramelise.
5. Scrape the roasted vegetables and all the tray juices into a large saucepan. Add 400ml of the stock, bring to a gentle simmer and cook for 10 minutes.
6. Reserve a few small basil leaves for serving. Add the remaining leaves and stalks to the pan, then remove it from the heat.
7. Blend with a stick blender until smooth. Alternatively, allow the mixture to cool slightly before using a jug blender; work in batches, vent the lid as directed by the manufacturer and avoid overfilling it with hot liquid.
8. Add more stock until the soup reaches your preferred consistency. Stir in the vinegar, taste and adjust the seasoning. Add the optional sugar only if the tomatoes remain noticeably sharp.
9. Ladle into warm bowls and finish with the reserved basil. Serve with toast, a baked potato or a simple cheese sandwich for a fuller meal.

Why roasting suits late-summer tomatoes

British tomatoes are usually at their most abundant and flavourful during the warmer harvest months. Their water content and acidity vary by type, so a mixed tray may produce a more interesting soup than perfectly uniform salad tomatoes.

Roasting evaporates some of the water while browning the natural sugars. It is particularly useful when tomatoes are ripe but taste slightly less intense than expected. The browned tray juices are valuable: scrape them into the saucepan rather than leaving them behind.

Fresh basil should go in near the end. Long boiling can dull its aroma and colour. There is no need to discard tender stalks because they blend smoothly and carry plenty of flavour.

For a chunkier result, pulse the blender briefly. For a refined texture, blend thoroughly and pass the soup through a sieve, although sieving removes some of the fibre and increases preparation time.

Easy adjustments without masking the tomatoes

Good seasonal tomatoes need little embellishment, but the recipe is flexible.

• Add half a chopped red chilli before roasting for gentle heat.
• Roast a small red pepper with the tomatoes for extra sweetness.
• Stir in cooked white beans before blending to make the soup more substantial.
• Use a little extra stock and add cooked orzo for a light tomato pasta soup.
• Finish each bowl with yoghurt, crème fraîche or basil oil rather than adding dairy to the whole batch.

Taste before adding sugar. Sweetness should balance excessive acidity, not turn the soup sugary. Vinegar may sound counterintuitive, but a small amount can sharpen tomatoes that taste flat; add it gradually.

The base recipe is vegan when made with suitable vegetable stock. It can also be gluten-free, but stock, bread and toppings should be checked individually.

Batch-cook now and freeze for winter

Double the ingredients to make eight servings, using two roasting trays so the tomatoes remain in a single layer. Crowding them into a deep dish traps steam and reduces browning. Swap the trays between oven shelves halfway through if they are colouring unevenly.

Let the finished soup cool promptly before transferring it to clean, freezer-safe containers. Portioning it into one- or two-serving amounts makes winter lunches easier and avoids defrosting more than you need. Leave a little expansion space at the top of rigid containers.

Label each portion with the name and freezing date. For the best flavour and texture, use it within three months. Defrost overnight in the refrigerator, then reheat in a saucepan until steaming hot throughout, stirring regularly. Add a handful of fresh basil after reheating if available; frozen basil in the soup may lose some of its bright aroma.

If freezer space is limited, simmer the blended soup for an extra 10–15 minutes to make a concentrated base. Freeze smaller portions, then add water or stock while reheating. This also makes the batch useful as a quick tomato sauce for pasta, beans or baked vegetables.

Serving and storage notes

Refrigerate leftover soup promptly in a covered container and use it within two days. Reheat only the amount required. A splash of stock can loosen soup that has thickened in storage.

For contrast, serve it with crunchy croutons, toasted seeds or chopped cucumber. A drizzle of oil adds richness, but the soup is satisfying without cream because the blended roasted vegetables naturally create body.

Source: Editorial research